What is Metabolic Age

What Is Metabolic Age

Have you have wondered, “What is metabolic age?” If you have, then you’re likely a person concerned about getting (or staying) lean, and you’re asking an important question!

And if you’ve ever spent substantial time looking up fitness information, you’ve likely come across this question.

According to research, metabolic age is very much a real thing. Our age can significantly impact the speed and effectiveness of the many bodily processes that make up our metabolism. And this includes an important function…maintaining a healthy weight.

The question is, what does this mean for us? More importantly, what can we do about it? 

What is Metabolic Age?

To understand this question, we first need to go over BMR – basal metabolic rate.

BMR represents the number of calories your body burns at rest every day. In other words, if you lie in your bed all day, don’t move a muscle, and don’t consume any foods or beverages, your body will still burn a specific number of calories to carry out its many processes.

Metabolic age represents your BMR compared to the average of people your age.

On its own, your metabolic age can’t give you the full picture because many factors go into BMR – for example, your size and muscular development. The larger you are, or the more muscle tissue you have, the higher your BMR will be. This is a simple biological fact as muscle burns more calories than fat.

But given that BMR alone doesn’t tell us that much, what else should we look at? Let’s see.

How Does Your Metabolism Affect Your Weight?

Metabolic AgeBesides BMR, we also have TEF, NEAT, and EAT. Together, these four components make up our daily energy expenditure.

  • Thermic effect of food (TEF) stands for the number of calories we burn to break down and absorb the foods we eat.
  • Exercise activity thermogenesis (EAT) stands for the number of calories we burn with dedicated exercise time.
  • Non-exercise activity thermogenesis (NEAT) stands for the number of calories we burn from every other activity – brushing our teeth, playing with our kids, and everything else you can think of.

Together with our BMR, these components make up our total daily energy expenditure (TDEE). This is an important number, and really where the proverbial rubber meets the road.

So long as we eat roughly the same number of calories as we expend, we get to maintain our weight. If we eat fewer calories than we burn, we lose weight. If we eat more calories than we burn, the excess gets stored, and we gain weight.

For example, if your TDEE is 3,000 calories, eating 2,500 per day will result in weight loss. In contrast, eating 3,000+ will result in weight gain.

Does Your Metabolism Change With Age?

Yes, your metabolism changes with age, but many people see it as something that can’t be influenced. In reality, age-related metabolic changes are most often caused by the drastic reduction in EAT and NEAT. In other words, we become less active, and we start burning fewer calories.

Besides that, we tend to lose muscle as we get older (due to sarcopenia), which further contributes to a lower metabolic rate. The question is, what can we do about it? Let’s see: (1)

How to Boost Your Metabolism (and Your Metabolic Age)

Boosting your metabolic rate is about influencing the individual components – most notably, TEF, EAT, and NEAT.

The best way to go about boosting your metabolic rate is to become more active and increase your EAT and NEAT, as both of these contribute to a healthy metabolism. For example, incorporate dedicated exercise three to four days – lift weights, do cardio, play sports, and more.

Besides, make a conscious effort to become more active:

  • Take the stairs
  • Leave your car and grab the bike instead
  • Play with your kids or grandkids
  • Stand instead of sitting

Can Certain Foods Boost Your Metabolism?

Protein has the highest thermic effect – around 15 to 30 percent. Meaning, if you eat 1,000 calories worth of protein, your body will expend between 150 and 300 to break it down and absorb it.

Improve Metabolic Age

This is why an important factor in staying lean is to eat protein with all (or most) of your meals. It’s also one of the reasons that low-carb diets are generally very effective for weight loss or weight control. (2)

An effective way to boost your metabolism through food is to start consuming more protein-rich foods: eggs, meats, fish, poultry, dairy, and similar.

In contrast, foods rich in carbs and fats aren’t great for boosting your metabolism because their thermic effect is much lower. For reference, carbs have a TE of about five to ten percent, and fats have a TE of zero to three percent.

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David Williams

A diet and fitness enthusiast, David is an ex-Army Airborne Ranger and Infantry soldier with decades of fitness and wellness experience. A West Point graduate with a degree in engineering, he focuses on technical research related to fitness, nutrition, and wellness. He loves the beach and working out, and spending time with his wife and daughters.

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  1. DerSarkissian, C. (2020). Sarcopenia (Muscle Loss With Aging): Symptoms, Causes, and Treatments. WebMD. https://www.webmd.com/healthy-aging/guide/sarcopenia-with-aging.
  2. Mayo Foundation for Medical Education and Research. (2020). Can a low-carb diet help you lose weight? Mayo Clinic. https://www.mayoclinic.org/healthy-lifestyle/weight-loss/in-depth/low-carb-diet/art-20045831.

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